* {
    margin: 0;
    padding: 0;
}

body {
    background: #16a085;
}

#bg {
    width: 100%;
    height: 100%;
    position: absolute;
    overflow: hidden;
}

.main {
    width: 530px;
    height: 250px;

    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    margin: auto;
    position: absolute;

    /* border: 1px solid brown; */

    /* overflow: hidden; */
    display: flex;
}

.item {
    height: 100%;
    width: 250px;
    border-radius: 6px;
    background-color: rgba(0, 0, 0, 0.2);
    flex-grow: 1;
    margin: 0 10px;
    overflow: hidden;
    cursor: pointer;
    transition: all 500ms;
}

.item:hover {
    background-color: rgba(0, 0, 0, 0.4);
}

.menu {
    padding-left: 10px;
    padding-right: 10px;
    padding-top: 210px;
    padding-bottom: 10px;
    height: 100%;
    transition: all 500ms;
}

.menu:hover {
    padding-top: 10px;
}

.menu summary {
    color: #E0E0E0;
    font-size: 18px;
    line-height: 40px;
}

.menu p {
    color: #B0B0B0;
    text-indent: 30px;
    line-height: 25px;
}

@media screen and (max-width:530px) {
    .main {
        flex-flow: column;
        height: 100%;
        width: 100%;
    }

    .item {
        width: auto;
        margin: 10px 10px;
        background-color: rgba(0, 0, 0, 0.2);
        border-radius: 6px;
    }

    .menu {
        padding-top: 10px;
    }
}